This study develops a force controlled manipulator which employs a new robot joint mechanism, named MIA : Mechanical Impedance Adjuster. The manipulator is suitable for carrying out human interactive tasks, because it can realize ideal joint compliance which is necessary for ensuring human's safety. It can also adapt to complicated working conditions by changing it's viscoelasticity characteristics, The research items in this study are listed as bellow ;1. A seven D.O.F.MIA arm and it's control system are developed. For evaluating control capabilities of the manipulator, impedance characteristics of the MIA mechanism are measured, After these basic evaluation, the arm system has improved in power, in order to carry out dexterous handling task by using the multiple fingered hand which is attached to the arm.2. An operating system is developed for realizing complicated manipulation which involves human-robot interaction, The system utilizes concept of the finite state automaton, and it can create various motions in adapting to changes of environmental conditions.3. For achieving speedy and accurate manipulation, an equation of motion of the MIA arm is analyzed by using the Lyapunov's stability criteria. The result shows that adjustment of damping coefficient is effective for maintaining the stability of the MIA arm. In addition, a double safety measure by using mechanism and control is proposed in consideration of safety of human whom robots collaborate with.4. An arm-hand coordination system is constructed by attaching the force control hand to the seven D.O.F.MIA arm. To evaluate force control capabilities in constraint conditions, experiments on human robot interaction are made, In the experiments, grasping motion of unknown shaped objects and hands over objects to human are adopted as examples of human interactive tasks. From the experimental results, high adaptability of the manipulator system and effectiveness of this study are confirmed.